THM 4T40-E

THM 4T40-E
INDEX
RANGE REFERENCE CHART .......................................................................
FLUID CHECKING PROCEDURE ..................................................................
LINE PRESSURE TEST ...................................................................................
TROUBLE CODE RETRIEVAL AND PCM LOCATION .......................................
TROUBLE CODE CHART AND DESCRIPTION ................................................
ELECTRONIC COMPONENTS AND DESCRIPTION ........................................
INTERNAL WIRE HARNESS SCHEMATIC ........................................................
ELECTRONIC COMPONENT RESISTANCE CHART .........................................
DIAGNOSTIC CHARTS ................................................................................
TCC SHUDDER DIAGNOSIS ........................................................................
OIL PASSAGE IDENTIFICATION ....................................................................
CHECKBALL LOCATIONS IN CHANNEL PLATE ..............................................
TRANSAXLE DISASSEMBLY ..........................................................................
COMPONENT REPAIR AND TRANSAXLE ASSEMBLY .......................................
FORWARD CLUTCH HOUSING ASSEMBLY ....................................................
DIRECT/COAST CLUTCH HOUSING ASSEMBLY .............................................
SELECTIVE THRUST WASHER MEASUREMENT ................................................
REVERSE INPUT CLUTCH AND 2ND ROLLER CLUTCH ....................................
INPUT SPEED SENSOR ASSEMBLY ................................................................
VALVE BODY ASSEMBLY ..............................................................................
PRESSURE SWITCH ASSEMBLY TEST PROCEDURE (OFF UNIT) ..........................
BEARING AND WASHER LOCATION CHART .................................................
TORQUE SPECIFICATIONS ..........................................................................
SPECIAL TOOLS .........................................................................................
"UPDATE SECTION" ....................................................................................
"Portions of materials contained herein have been reprinted under
license from General Motors Corp, Service & Parts Operations."
The information and part numbers contained in this booklet have
been carefully compiled from industry sources known for their
reliability, but ATSG does not guarantee its accuracy.
Copyright © ATSG 1995
AUTOMATIC TRANSMISSION SERVICE GROUP
18639 SW 107TH AVENUE
MIAMI, FLORIDA 33157
(305) 670-4161
Copyright © ATSG 1999
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16
21
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46
48
61
71
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91
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108
119
120
121
Updated
April, 2003
INTRODUCTION
THM 4T40-E
We wish to thank General Motors Corporation for the information and illustrations that have made this booklet
possible. This booklet contains general description and the procedures necessary to repair, service, or overhaul
the THM 4T40-E electronic overdrive automatic transaxle. This unit was first introduced in the 1995 Chevrolet
Cavalier and Pontiac Sunfire vehicles, and will eventually replace the THM 125C (3T40).
The THM 4T40-E is a fully automatic front wheel drive transaxle. It provides park, reverse, neutral, and 4
forward speeds including overdrive. The shift pattern is controlled electronically with 2 shift solenoids that
recieve a ground signal from the Powertrain Control Module (PCM). The PCM will vary shift points, as it is
constantly interpreting numerous electronic signals from various operational sensore located on the vehicle.
The PCM also controls apply and release of the Torque Converter Clutch. Line pressure and shift feel are also
controlled electronically with a Pressure Control Solenoid (PCS) located on the valve body and is dependant on
TPS and VSS signals.
No part of any ATSG publication may be reproduced, stored in any retrieval system or transmitted in any form or
by any means, including but not limited to electronic, mechanical, photocopying, recording or otherwise,
without written permission of Automatic Transmission Service Group. This includes all text illustrations,
tables and charts.
"Portions of materials contained herein have been reprinted under
license from General Motors Corp, Service & Parts Operations."
The information and part numbers contained in this booklet have
been carefully compiled from industry sources known for their
reliability, but ATSG does not guarantee its accuracy.
Copyright © ATSG 1995
DALE ENGLAND
JIM DIAL
FIELD SERVICE CONSULTANT
TECHNICAL CONSULTANT
WAYNE COLONNA
ED KRUSE
TECHNICAL SUPERVISOR
TECHNICAL CONSULTANT
PETER LUBAN
GREGORY LIPNICK
TECHNICAL CONSULTANT
TECHNICAL CONSULTANT
JON GLATSTEIN
DAVID CHALKER
TECHNICAL CONSULTANT
TECHNICAL CONSULTANT
ROLAND ALVAREZ
JERRY GOTT
TECHNICAL CONSULTANT
TECHNICAL CONSULTANT
GERALD CAMPBELL
MIKE SOUZA
TECHNICAL CONSULTANT
TECHNICAL CONSULTANT
AUTOMATIC TRANSMISSION SERVICE GROUP
18639 SW 107TH AVENUE
MIAMI, FLORIDA 33157
(305) 670-4161
1
Technical Service Information
NO. 1
NO. 4
THM 4T40-E
1995-1996 MODELS ONLY
CHECKBALL LOCATIONS
NO. 7
NO. 2
NO. 6
NO. 5
NO. 3
NO. 1
NO. 4
NO. 6
THM 4T40-E
1997-UP MODELS ONLY
CHECKBALL LOCATIONS
NO. 7
NO. 2
NO. 5
NO. 3
Copyright © 2003 ATSG
Figure 41
AUTOMATIC TRANSMISSION SERVICE GROUP
46
Technical Service Information
See Page 46 In This Manual
For "Updated" Checkball Locations.
Figure 60
Figure 58
Figure 61
Figure 59
AUTOMATIC TRANSMISSION SERVICE GROUP
53
Technical Service Information
See Page 46 In This Manual
For "Updated" Checkball Locations.
See Page 121 In This Manual
For "Updated" Channel Plates.
Figure 171
Figure 169
Figure 170
AUTOMATIC TRANSMISSION SERVICE GROUP
94
"UPDATE SECTION"
THM 4T40-E
TRANSAXLE CASE, CHANNEL PLATE AND
CHECKBALL LOCATION CHANGES FOR 1997
CHANGE: Beginning in the middle of the 1997 model year, the transaxle case, channel plate and the checkball
locations were changed on all THM 4T40-E transaxles, that may create some confusion for
service.
REASON: Improved clutch durability, and improved 4-2 downshift.
PARTS AFFECTED:
(1) TRANSAXLE CASE - Added boss and the second threaded hole to the case in the area shown in
Figure 2, to accommodate valve body bolt and channel plate changes for improved clamping. The
previous design case, with the single boss and hole is shown in Figure 1.
(2) CHANNEL PLATE - New casting with an added boss, and one of the threaded holes in the channel
plate changes to a non-threaded hole to accomodate the valve body bolt changes for improved
clamping force. The previous design channel plate is shown in Figure 3, and the new design
channel plate is shown in Figure 4.
(3) CHECKBALL LOCATIONS - The number 6 checkball moves from the direct clutch apply
circuit, and into the 2-3 accumulator circuit. There were no changes in worm track configuration,
however we also show the "Threaded" hole that changed to a "Non-Threaded" hole in the channel
plate. Refer to Figure 5 for 1995-1996 checkball locations, and Figure 6 for the 1997-Up
checkball locations.
(4) SPACER PLATE - The number 45 exhaust passage in the spacer plate has changed from a
rectangular hole to a small oval hole, as shown in Figure 7.
(5) DRIVEN SPROCKET SUPPORT - Ball capsule added in the direct clutch circuit to act as an air
bleed to improve direct clutch apply, as shown in Figure 8.
INTERCHANGEABILITY:
NONE of the parts listed above will interchange with previous design level transaxles. Any
transaxle using the ball capsule in the direct clutch circuit must use the 1997 channel plate and all
associated parts listed above.
AUTOMATIC TRANSMISSION SERVICE GROUP
121
"UPDATE SECTION"
1995-1996 TRANSAXLE CASE
Single Threaded Hole
Figure 1
1997-UP TRANSAXLE CASE
Double Threaded Holes
Figure 2
AUTOMATIC TRANSMISSION SERVICE GROUP
122
"UPDATE SECTION"
1995-1996 CHANNEL PLATE
Threaded
Bolt Hole
Figure 3
1997-UP CHANNEL PLATE
Non-Threaded
Bolt Hole
Added Boss
Figure 4
AUTOMATIC TRANSMISSION SERVICE GROUP
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"UPDATE SECTION"
THM 4T40-E 1995-1996 MODELS ONLY
CHECKBALL LOCATIONS
NO. 1
NO. 4
"Threaded" Hole
in Channel Plate
Located Here.
NO. 7
NO. 2
NO. 1
NO. 2
NO. 3
NO. 4
NO. 5
NO. 6
NO. 7
NO. 6
NO. 5
NO. 3
SEPERATES LO/PRN FLUID CIRCUITS.
FORCES 2-3 DRIVE FLUID THRU ORIFICE #3 TO CONTROL 1-2 SHIFT FEEL.
FORCES INTERMEDIATE BAND APPLY OIL THRU ORIFICE #8 FOR APPLY FEEL.
FORCES ACCUMULATOR OIL THRU ORIFICE #24 TO THE 1-2 ACCUMULATOR.
FORCES 3-4 DRIVE OIL THRU ORIFICE #26 TO CONTROL 2-3 SHIFT FEEL.
FORCES EXHAUSTING DIRECT CLUTCH OIL THRU ORIFICE #25 TO CONTROL RELEASE. OF DIRECT CLUTCH.
FORCES ACCUMULATOR OIL THRU ORIFICE #28 TO THE 3-4 ACCUMULATOR.
Figure 5
AUTOMATIC TRANSMISSION SERVICE GROUP
124
"UPDATE SECTION"
THM 4T40-E 1997-UP MODELS ONLY
CHECKBALL LOCATIONS
NO. 1
NO. 4
NO. 6
"Non-Threaded" Hole
in Channel Plate
Located Here.
NO. 7
NO. 2
NO. 1
NO. 2
NO. 3
NO. 4
NO. 5
NO. 6
NO. 7
NO. 5
SEPERATES LO/PRN FLUID CIRCUITS.
FORCES 2-3 DRIVE FLUID THRU ORIFICE #3 TO CONTROL 1-2 SHIFT FEEL.
FORCES INTERMEDIATE BAND APPLY OIL THRU ORIFICE #8 FOR APPLY FEEL.
FORCES ACCUMULATOR OIL THRU ORIFICE #24 TO THE 1-2 ACCUMULATOR.
FORCES 3-4 DRIVE OIL THRU ORIFICE #26 TO CONTROL 2-3 SHIFT FEEL.
FORCES ACCUMULATOR OIL THRU ORIFICE #27 TO THE 2-3 ACCUMULATOR.
FORCES ACCUMULATOR OIL THRU ORIFICE #28 TO THE 3-4 ACCUMULATOR.
Figure 6
AUTOMATIC TRANSMISSION SERVICE GROUP
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NO. 3
"UPDATE SECTION"
1995-1996
Spacer Plate
THE NO. 45 PASSAGE CHANGED
FROM RECTANGULAR TO OVAL
1997
Spacer Plate
Figure 7
AUTOMATIC TRANSMISSION SERVICE GROUP
126
"UPDATE SECTION"
THM 4T40-E 1997-UP MODELS ONLY
DRIVEN SPROCKET SUPPORT
ADDED BALL CAPSULE
Figure 8
AUTOMATIC TRANSMISSION SERVICE GROUP
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"UPDATE SECTION"
Notes
AUTOMATIC TRANSMISSION SERVICE GROUP
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